Audi 80/Avant (B4)

since 1991-1995 of release

Repair and car operation

Audi 80/Avant
+ Technical specification
+ Engines
+ System of production of the fulfilled gases
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
+ injection System
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
- Brake system
   Check of brake mechanisms
   Brake liquid
   Check of level of brake liquid
   Check of tightness of brake system
   Replacement of brake liquid
   Disk brake mechanisms
   Measurement of thickness of blocks of the disk mechanism
   Control of a condition of brake disks
   Replacement of blocks of disk brake mechanisms
   Drum-type brake mechanism
   Measurement of brake shoes of the drum-type mechanism
   Check of a course of a pedal of a brake
   Disk brake mechanism of back wheels
   Measurement of thickness of blocks of back disk brakes
   Check of a free wheeling of the lever of the parking brake
   Main brake cylinder
   Amplifier of brakes
   Check of the amplifier of brakes
   Regulator of brake forces
   Repair of a hydraulic drive of brakes
   Pumping of brake system
   List of malfunctions
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrosystem
+ ignition System
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications

Replacement of blocks of disk brake mechanisms

Essentially on the right or at the left both blocks are necessary to replace. It is possible to apply only blocks with «The general admission to operation» (in German «Allgemeine Betriebserlaubnis» – ABE).

Brake Girling mechanism: to turn out only the bottom fixing bolt (2) cases of a support of the disk brake mechanism. To hold a napravlyashchy bolt. The top fastening (1) remains untouched. At installation to apply new самоконтрящийся a fixing bolt!

Brake Ate mechanism: after removal of a cap (3) to weaken the bottom bolt with an internal shestigrannik in protective plugs (4).

In the brake mechanism of the producer of Girling two are necessary for replacement of blocks in total new самоконтрящихся a bolt. In most cases they enter into a set with brake shoes – to check! If the brake mechanism from the producer of Ate, bolts be not required to you.

As pistons in supports of brake mechanisms with increasing wear of blocks leave everything farther, before installation of new, thicker blocks it is necessary to put them into place. Thus brake liquid is squeezed out via the pipeline in a receiver. If in the past the excessive amount of unnecessary liquid was added, this surplus now needs to be pumped out. Otherwise acting brake liquid will spill on the metal details located in a motor compartment. It is necessary to apply to pumping out only absolutely pure pipette or an old medical syringe – at all do not suck away a mouth!


  1. The car to raise in front and to fix.
  2. To remove a wheel.
  3. To turn a steering wheel that it was possible to reach blocks easily.
  4. Brake Ate mechanism: to remove a cap on bracket inside. To insert a face key in opened now an internal shestigrannik of a bolt and to weaken it.
  5. To unscrew only the bottom bolt.
  6. To extend a bolt, to cast away a bracket of a support of the disk brake mechanism up or – if both bolts were removed – to remove.
  7. The removed bracket to suspend on a wire to an amortization rack.
  8. Brake Girling mechanism: to unscrew only the bottom fixing bolt of the case of a support of the disk brake mechanism, holding thus directing bolt for a six-sided head.
  9. To cast away a bracket upward.
  10. Both versions: on the right and at the left to take out blocks from directing tires.
  11. By means of a clamp to wring out a rod inside. In order that the piston did not warp or damaged, put on a lock ring a small plate.
  12. At the two-piston brake mechanism it is necessary the same way to wring out both brake rods together or separately.
  13. Pay attention to the correct landing of a heat-shielding guard in the piston cylinder.
  14. To establish new blocks.
  15. To put into place a support.
  16. Brake Ate mechanism: to tighten directing bolt the moment of 25 N • m and again to put on a cap.
  17. Brake Girling mechanism: to tighten bottom (the new!) fixing bolt moment of 35 N • m. The top bolt not дозатягивать, differently will stop самоконтрящееся action. Hold directing bolt with a thin rozhkovy wrench, differently it will clamp, and in this case force of an inhaling will be incorrect.
  18. After assembly several times press a brake pedal, until then while blocks will not nestle on brake disks. Otherwise there will be no brake influence!

 Help: when passing the first 500 km with new brake shoes brake whenever possible more carefully.

Removal of a forward support of the disk brake mechanism

The Dvukhporshnevy disk brake mechanism with a floating bracket of 6-cylinder models

1–case of a support of the disk brake mechanism;
2–brake piston;
3–brake shoes;

4–the bottom directing;
5–brake disk;
6–support of the brake mechanism.

The case of a support of the disk brake mechanism (1) of 4-cylinder model will cast away up after removal of the bottom fastening (4). Blocks (3) for the present stand in the directing. Further are visible:

2–a heat-shielding guard in the brake piston;
5–brake disk;
6–support of the brake mechanism.

Each of forward supports of disk brake mechanisms is strengthened on an amortization rack by two so-called corrugated bolts. At these bolts behind a six-sided head the corrugated surface preventing casual easing or loss of a bolt is located. By no means it is impossible to replace these corrugated bolts usual!


  1. To remove a wheel.
  2. To remove brake shoes.
  3. To weaken fixing bolts of a support of the brake mechanism.
  4. To hang out a support of the brake mechanism with the connected hose so that the hose was not tense.
  5. Or to remove a brake hose or a tube.
  6. To press a pedal of a brake and to hold it, to prevent an effluence of brake liquid.
  7. Before installation to clear corrugated surfaces of ridge bolts.
  8. To tighten corrugated bolts the moment of 125 N • m.
  9. Again to establish a brake hose or a tube.
  10. To remove air from brake system in case the brake pipeline or a hose was removed.
  11. Before a start of motion several times to press a brake pedal until the normal course of a pedal will be established.

Replacement of cuffs of brake pistons

On an illustration the piston of the cylinder of the disk brake mechanism move by means of a clamp in order that it was possible to establish new brake shoes. For protection we enclosed a small wooden plate. The support of the brake mechanism of the producer of Girling removed for the photo usually remains fixed on the top bolt.

If the cuff of the brake piston in a support of the disk brake mechanism was damaged, you need to replace as soon as possible it, differently the brake piston soon will start to jam because of dirt and corrosion. The cuff can be got only complete with a sealing ring of the brake piston. For installation of both details it is necessary to take the piston from the case of the brake cylinder.

It is for safety reasons better to charge this work of a workshop. For example, to remove a support of the disk brake mechanism and to bring it to a workshop.

Replacement of a forward brake disk

Brake disks need to be changed from both parties at the same time. Unilateral replacement will lead to non-uniform brake action.


  1. To disconnect a support of the disk brake mechanism and to strengthen it a wire on a body; hoses remain connected.
  2. To turn out a bolt with a crosswise shliyets (near an opening for wheel bolts).
  3. To process a bolt means for removal of a rust or to apply pulse болтоверт.
  4. Now it is possible to remove a hand a brake disk from a wheel nave.
  5. If it приржавел to help in sharp blows of a hammer but only in case this disk in any case should change.
  6. Before installation of a new brake disk to clear a prileganiye surface on a wheel nave.